During 1988 many engineers and field technicians experienced irregularities when trying to correlate the fixed-wing airplane-type CLI FLYOVER test data with the results of their ground surveys. The inconsistencies seemed to be related to the fact that the test dipole was not operating in open space, the high cruising speed of the aircraft and the cockpit's limited visibility. During a helicopter flyover the test antenna is front-mounted, in open space. The helicopter can cruise at moderate speed and the cockpit's vertical visibility is unlimited. The presentation compares and analyzes the radiation pattern characteristics of the test dipole under the fuselage and in front of the aircraft. This is followed by a discussion of the triangulation method to determine exact leakage source locations. Finally, a few observations are presented about digital leakage recordings and aircraft position identification methods.